Who invented the quartz clock in 1927?

A quartz clock is a clock that uses an electronic oscillator that is regulated by a quartz crystal to keep time. The first quartz clock was built in 1927 by Warren Marrison and J. W. Horton at Bell Telephone Laboratories. Since the 1980s, when the advent of solid-state digital electronics allowed them to be made compact and inexpensive, quartz timekeepers have become the world's most widely used timekeeping technology, used in most clocks and watches, as well as computers and other appliances that keep time.